the issue got attention last week when they showed a subway sandwich that did not measure 12 estimates. he's eaten about 50 sandwich as year since he was 18. he says now i feel cheated. i feel like he has a lot of time on his hands. >>> doctors often worn patients that eating grapefruit can interfere with their medication. now we learn that's not the only food we need to other about. dr. holly phillips is here at the table. let's start with grapefruit. i learned the hard way lipitor and grapefruit does not mix. >> we have known for a while there's interaction with a few medicine bus there's a new review out that says it's not a few, it's 85. and these are the big drugs, things we -- everyone is prescribes, things for blood praerks things for cholesterol, and even birth control pills and the interactions are severe from kidney failure to internal bleeding. the problem is bigger than we thought. >> what is it in the grapefruit. >> really the way that it works to be very simple about it. you take a pill and it goes into your intestine to be absorbed into the bloodstream. your intestine ha